python07

__init__.py

from . import p1
from . import p2  # 理解：import p2 先导入 p2 文件， 然后该文件的内容全要 from .
#
# 告诉调用者，哪些文件需要使用

p1.py

def sum(a,b):print(a + b)

p2.py

def max(a,b):if a > b:print(a)else:print(b)

 py04.py

# 导入py的文件夹，文件夹中的init文件说明了要导出的是p1和p2 两个文件，只需要导py文件夹即可
import pypy.p1.sum(1,6)py.p2.max(9,2)

 py70.py

def sum(a,b):print(a + b)
def max(a,b):if a > b:print(a)else:print(b)

 py72.py

# # 部分导入
# from py70 import sum
# sum(1,5)# 给python文件起名字的时候，千万不要使用关键字,因为程序会优先寻找你文件夹中的这个文件，再去找系统的包
import random
ran1 = random.randint(1,10)
print(ran1)

 py73.py

def fn1():print(__name__)
# 自己文件中打印__name__   结果是__main__fn1()

 py74.py

import py73 as p73p73.fn1()   # 其他文件调用后，结果就是这个文件的名字

75.文件读写

# 方法1 不推荐使用，繁琐
# open("./1.txt",)    # ./和不写，都代表从当前文件目录去找内容
# "r" 读取 encoding="utf8"  设置中文编码（国际编码）让中文可以正常显示
file1 = open(r".\1.txt","r",encoding="utf8")
print(file1.read())
file1.close()   # 写了open 最后就要写close关闭文件

# 方法2 强烈推荐使用 系统自带close
with open(r".\1.txt","r",encoding="utf8") as file1:data = file1.read()
print(data)

76写入文件：

# # 向文件中写入内容  "w" 代表写入(覆盖)
# #                "a" 代表 追加写入
# with open(r"./2.txt","w",encoding="utf8") as file1:
#     file1.write("外星人你好，我是AI钢铁侠，请问你来自哪里")# 如果文件存在，就是进行写入，如果文件不存在，新建文件，再写入 会把原来的内容写入（覆盖写入）
with open(r"./4.txt","w",encoding="utf8") as file1:file1.write("外星人你好，我是AI钢铁侠，请问你来自哪里！")# 如果文件存在，"a" 代表 追加写入   不存在就是新建文件然后再写入
with open(r"./4.txt","a",encoding="utf8") as file1:file1.write("--你好新同学")with open(r"./4.txt","w",encoding="utf8") as file1:file1.write("-------------- hello world ------------------")# 练习1 改写文件中的内容   1.txt有python 改成c
# 1.读取1.txt内容
with open(r"./1.txt","r",encoding="utf8") as file1:data = file1.read()     # 读取内容存到data变量中# print(data)data = data.replace("python","c") # 修改完毕后的值 把文件中的python替换为c# print(data)
with open(r"./1.txt","w",encoding="utf8") as file2:file2.write(data)# 练习2 合并文件：1.txt 和 2.txt 合并到 66.txt
# 1.读取两个文件的内容
with open(r"./1.txt","r",encoding="utf8") as file1:data_1 = file1.read()with open(r"./2.txt","r",encoding="utf8") as file2:data_2 = file2.read()# 两个文件的内容合并
with open(r"./66.txt","a",encoding="utf8") as file3:# 读取的内容是字符串类型，只需要进行加法即可file3.write(data_1 + data_2)

77按行读取：

# with open(r"./1.txt","r",encoding="utf8") as file1:
#     # 因为我想一行一行读取，把代码写在while死循环中，读到最后位置了，我再让循环退出
#     while 1:
#         txt = file1.readline()  # 一行一行读取
#         if txt == "":    #读到最后位置
#             break   # 后续不用操作了，直接break彻底退出
#         else:
#             print(txt,end="")   # print自带换行，加end=""取消# with open(r"./1.txt","r",encoding="utf8") as file1:
#     while 1:
#         txt = file1.readline()
#         if txt == "":
#             break
#         else:
#             print(txt,end="")# 练习 读取一个文件的偶数行
with open(r"./66.txt","r",encoding="utf8") as file1:num = 0 # 计数器while 1:txt = file1.readline()if txt == "":breakelse:# 计数器加1num += 1# 偶数才行if num % 2 == 0:print(txt,end="")# 练习2 读取一个文件的奇数行
with open(r"./66.txt","r",encoding="utf8") as file2:num = 0while 1:txt = file2.readline()if txt == "":breakelse:num += 1if num % 2 == 1:print(txt,end="")

78读取json文件

import json     # 导入json包
with open(r"./json01.json","r",encoding="utf8") as file_json:data = json.load(file_json)     # json.load()  读取json的数据 括号里面是 重命名后的file_json文件print(data)
print(type(data))   # json数据读取到python中，类型就是dict字典类型

 json01.json

{"name": "李老师", "age": 20, "isMan": true, "scholl": null, "address": {"country": "中国", "city": "山东", "street": "丰台"}, "score": [82, 88, 100], "link": [{"name": "en_mobile", "url": "www.baidu.com"}, {"name": "en_pc", "url": "www.taobao.com"}], "hehe": "呵呵", "haha": "哈哈"}

79写入json

# import json
# # 准备dict字典数据
# data = {
#     "name":"张三",
#     "age":18,
#     "addr":"北京"
# }
#
# with open(r"./my.json","w",encoding="utf8") as file_json:
#     json.dump(data,file_json,ensure_ascii=False)
#     # ensure_ascii=False 让中文正常显示，不写就会当做unicode码展示import json
# 绝对路径：（相对于电脑的） 具体在电脑哪个文件夹下 E:\QHMS\python\07\代码\json01.json# 相对路径：根据当前文件去寻找其他文件的方式,叫  相对路径查找（相对路径是相对文件自己的）如下：
# 上级   ./ 当前目录     ../ 上一级目录    ../../ 上两级目录
# 下级    文件夹1/文件夹2
#            文件路径        读      国际码
with open(r"E:\QHMS\python\07\代码\json01.json","r",encoding="utf8") as file_json:json_data = json.load(file_json)print(json_data["address"]) # 拿字典类型数据的语法规则来使用json_data["age"] = 20   # 修改键值json_data["address"]["city"] = "山东" # 修改键值json_data["haha"] = "哈哈"    # 原数据中没有这个键名，就相当于新增了一个键和值with open(r"./json01.json","w",encoding="utf8") as file_json2:json.dump(json_data,file_json2,ensure_ascii=False)    # json.dump("要写入的数据", "起别名后的文件名", ensure_ascii=False)

my.json

{"name": "张三", "age": 18, "addr": "北京"}